Deny 2018 idiom lints (#1108)

This lint is allow by default, which is why this wasn't spotted earlier.
It's denied by rust-lang/rust, so it's good to warn about it here so it
can be fixed more quickly.

Author: jyn514

crates/assert-instr-macro/src/lib.rs

@@ -7,6 +7,7 @@
 //! The procedural macro here is relatively simple, it simply appends a
 //! `#[test]` function to the original token stream which asserts that the
 //! function itself contains the relevant instruction.
+#![deny(rust_2018_idioms)]
 
 extern crate proc_macro;
 extern crate proc_macro2;
@@ -177,7 +178,7 @@ struct Invoc {
 }
 
 impl syn::parse::Parse for Invoc {
-    fn parse(input: syn::parse::ParseStream) -> syn::Result<Self> {
+    fn parse(input: syn::parse::ParseStream<'_>) -> syn::Result<Self> {
         use syn::{ext::IdentExt, Token};
 
         let mut instr = String::new();

crates/core_arch/src/lib.rs

@@ -2,6 +2,7 @@
 #![allow(improper_ctypes_definitions)]
 #![allow(dead_code)]
 #![allow(unused_features)]
+#![deny(rust_2018_idioms)]
 #![feature(
     asm,
     const_fn,
@@ -68,9 +69,6 @@ extern crate std;
 #[cfg(test)]
 #[macro_use]
 extern crate std_detect;
-#[cfg(test)]
-extern crate stdarch_test;
-
 #[path = "mod.rs"]
 mod core_arch;
 

crates/core_arch/src/x86/avx512vpclmulqdq.rs

@@ -9,7 +9,7 @@ use crate::core_arch::x86::__m256i;
 use crate::core_arch::x86::__m512i;
 
 #[cfg(test)]
-use crate::stdarch_test::assert_instr;
+use stdarch_test::assert_instr;
 
 #[allow(improper_ctypes)]
 extern "C" {

crates/core_arch/src/x86/fxsr.rs

@@ -87,7 +87,7 @@ mod tests {
     }
 
     impl fmt::Debug for FxsaveArea {
-        fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
             write!(f, "[")?;
             for i in 0..self.data.len() {
                 write!(f, "{}", self.data[i])?;

crates/core_arch/src/x86/pclmulqdq.rs

@@ -8,7 +8,7 @@
 use crate::core_arch::x86::__m128i;
 
 #[cfg(test)]
-use crate::stdarch_test::assert_instr;
+use stdarch_test::assert_instr;
 
 #[allow(improper_ctypes)]
 extern "C" {

crates/core_arch/src/x86/xsave.rs

@@ -196,7 +196,7 @@ mod tests {
     }
 
     impl fmt::Debug for XsaveArea {
-        fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
             write!(f, "[")?;
             for i in 0..self.data.len() {
                 write!(f, "{}", self.data[i])?;

crates/core_arch/src/x86_64/fxsr.rs

@@ -87,7 +87,7 @@ mod tests {
     }
 
     impl fmt::Debug for FxsaveArea {
-        fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
             write!(f, "[")?;
             for i in 0..self.data.len() {
                 write!(f, "{}", self.data[i])?;

crates/core_arch/src/x86_64/xsave.rs

@@ -164,7 +164,7 @@ mod tests {
     }
 
     impl fmt::Debug for XsaveArea {
-        fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
             write!(f, "[")?;
             for i in 0..self.data.len() {
                 write!(f, "{}", self.data[i])?;

crates/simd-test-macro/src/lib.rs

@@ -2,6 +2,7 @@
 //!
 //! This macro expands to a `#[test]` function which tests the local machine
 //! for the appropriate cfg before calling the inner test function.
+#![deny(rust_2018_idioms)]
 
 extern crate proc_macro;
 extern crate proc_macro2;

crates/std_detect/src/detect/os/linux/cpuinfo.rs

@@ -17,7 +17,7 @@ impl CpuInfo {
         })
     }
     /// Returns the value of the cpuinfo `field`.
-    pub(crate) fn field(&self, field: &str) -> CpuInfoField {
+    pub(crate) fn field(&self, field: &str) -> CpuInfoField<'_> {
         for l in self.raw.lines() {
             if l.trim().starts_with(field) {
                 return CpuInfoField::new(l.split(": ").nth(1));